Gas turbine engines have an arrangement of fuel injectors to supply fuel into the combustion chamber of the gas turbine engine and have a fuel manifold to supply fuel to the fuel injectors. In operation the fuel injectors are subjected to relatively high temperatures due to their proximity to the combustion chamber whereas the fuel manifold is subjected to relatively cold temperatures due to the relatively cold fuel within the fuel manifold which is supplied from the fuel manifold to the fuel injectors.
Thermal management of the fuel manifold and fuel injectors is required.
Fuel injectors have been provided with flexible internal fuel pipes or have been provided with internal sliding joints. Fuel injectors with flexible internal fuel pipes are bulky and it is difficult or impossible to inspect fuel injectors with flexible internal fuel pipes to determine whether they have failed. Fuel injectors with internal sliding joints invariably leak internally and the leakage of fuel leads to coking and gumming of the fuel with the possibility of deformation of the fuel injector and again it is difficult or impossible to inspect fuel injectors with internal sliding joints to determine whether they have failed.
Fuel manifolds have been made flexible by constructing the fuel manifold using fibre reinforced polymer pipes or by constructing portions of the fuel manifold from curved metal pipes, called pigtails. Fuel manifolds constructed from fibre reinforced polymer pipes are bulky and are difficult to fire proof. Fuel manifolds constructed from curved metal pipes are fragile, susceptible to handling damage, suffer from vibration and require extensive use of clips, or other types of fasteners, to secure the metal pipes to the gas turbine engine casing to reduce vibration.
Therefore the present invention seeks to provide a novel fuel manifold and fuel injector arrangement which reduces or overcomes the above mentioned problem.